Telegraph sending key



Dec. 8, 1964 w. H. sToUT 3,160,705

TELEGRAPH SENDING KEY Filed July 17, 1962 M,MMW%.

ATTORNEYS.

un "n United States Patent Oii ice 3,160,705 Patented Dec. 8, 1964 3,160,705 TELEGRA?H SENDEN@ KEY William H. Stout, PD. Eux 415, imperial, la. Filed lnly 17, 1962, Ser. No. 210,446 1 Claim. (Cl. IWL-108) This invention relates to keys for sending messages by tclegraphic or wireless code, and more particularly t means for opening the electric contacts of the key after they have been closed by the operator.

Such keys include a pivoted lever that carries an elec tric contact which engages a stationary electric contact to complete an electric circuit when one end of the lever is swung laterally or pressed down. The common way of separating the contacts is by means of a coil spring. To vary the sensitivity of the instrument to the operators touch, the spring sometimes is made adjustable to exert more or less opening force on the pivoted lever. lowever, expert operators often iind it difficult to adjust the spring in a manner that will give them the precise action of the key that they desire.

lt is among the objects of this invention to provide a telegraph sending key which can be adjusted to perform in any manner desired by the operator, and which does not utilize springs for opening the contacts.

ln accordance with this invention a telegraph key lever is pivotally mounted on a base and carries an electric Contact. The lever is adapted to be swung manually in one direction by an operator to move its contact into engagement with a stationary electric contact mounted on the base close to the movable contact. To separate the contacts kwhen the operator releases the lever, magnetic means are provided that urge the lever to swing in a contact-opening direction. Preferably, the magnetic means consist of a pair of permanent magnets, which may be adjusted toward and away from each other. Also, it is desirable to be able to rotate one of the magnets to vary its attraction or repulsion of the other magnet.

The preferred embodiment of'the invention is illustrated in the accompanying drawings, in which FIG. l is a plan View of my key;

FIG. 2 is a side View thereof; and

FiGS. 3 and 4 are vertical cross sections taken on the lines Illlil and lV-IV of FlG. l.

Referring to the drawings, an electronic type key is shown, although the invention is equally applicable to a single lever press-down type telegraph key. With an electronic key there are two sets of electric contacts, one set for the dots and the other set for the dashes of the code. The movable contacts are moved horizontally. For this purpose, a pair of spaced parallel horizontal bar levers 1 are pivotally connected on vertical axes to a suitable base 2, which may be metal. Thus, as shown in FIG. 3, each lever may be provided near one end with aligned upper and lower pivot pins 3 seated in bearings 4 and S secured to the base and to a yoke d mounted on the base and straddling both bars. Finger pieces or paddles 7 are attached to the same end of the levers to permit an operator to swing them on their pivots. Between the levers at their opposite end is a stop 8 that is fastened to the base to limit the distance the levers can move toward each other. This end of each lever carries an outwardly facing electric contact 9 that is spaced a short distance from a stationary electric contact 1d mounted on the inner end or" a horizontal adjusting screw 11 extending through a post 12 mounted on the base at the outer side of the adjacent lever. The end of the base near the stationary contacts also supports three terminals. The center ground terminal 13 is electrically connected through a wire on the base with the levers and the contacts carried by them. Each of the end terminals 14 is electrically connected with the adjacent stationary contact 10. The three terminals are connected in the usual manner with an electronic cir 'cuit (not shown), with which the key is used. When either of the paddles is swung toward the other, the contact at the opposite end of the lever will engage the adjacent stationary contact and close an electric circuit. Depending upon which set of contacts is closed, either a dot or a dash will be transmitted.

It is a feature of this invention that levers 1 are Ieturned to their normal position against stop 8 by nonmechanical means every time paddles 7 are released. Specifically, magnetic means are used for this purpose. Although electromagnets could be used if desired, it is simpler and cheaper to use permanent magnets. Accordingly, attached to one side of each lever is a permanent magnet 16 that is spaced a short distance from a similar stationary magnet 17 mounted on the base. Each pair of magnets are arranged to react on each other to urge the adjoining lever to swing its contact away from the stationary contact with which it cooperates. For this purpose the magnets could be so arranged that magnetic attraction of one for the other would pull the contacts apart, but the preferred way of creating the desired magnetic force is by repulsion rather than attraction. lf attraction is used, it is least effective at the moment the contacts separate and then it increases as one magnet moves nearer the other. Since it is highly desirable to have as quick a contact break as possible, magnetic repulsion is preferred because the magnets are closest together while the contacts are in engagement and therefore the repulsive force is strongest at that time. To arrange the magnets to repulse each other, one magnet 16 is fastened to the outer side of each lever on the contact side of its pivot; that is, in the arrangement shown, the magnet is between the pivot and the lever contact 9. The outer face of this magnet is spaced from the inner face of the cooperating magnet 17, which may be mounted on the inner end of a horizontal screw 1S extending through a vertical post 19 mounted on base 2. The poles of the two magnets at each side of the key are arranged so that the magnets will repulse each other. Therefore, the moment the operator releases a paddle of the key, the movable magnet at that side of the key will be repulsed by the adjacent stationary magnet and swing the lever inward against the center stop.

The strength of the repulsive force can be increased by turning screw 1S to move the stationary magnet toward the adjacent movable one, or it can be reduced by turning the screw in the opposite direction. An even hner adjustment can oe obtained by using U-shape or horseshoe magnets as shown, wherein the north and south poles of the movable magnets 16 will face outward and the poles of the stationary magnets will face inward. Normally, the north poles in each set will be directly opposite each other. When the screw is turned, it will alter the position of the north and south poles of the stationary magnet rotationally relative to the poles of the movable magnet, thereby providing another and ner adjustment of the magnetic force between the two magnets.

With this arrangement, any desired opening force can be exerted on the contacts, and the greatest force will always be exerted at the moment of break where it is most important. The levers swing extremely free because there `are no restraining springs connected to them. With a double lever key as shown in the drawings, the two sets of magnets can be set differently from each other so that the feel of the levers is individually adjustable. That is not possible when a single compression spring is used. This invention also allows closer settings of contact points, without producing contact bounce, than is possible with spring controlled levers. A very high rate of message transmission can be obtained with this key by an expert operator.

According to the provisions of the patent statutes, I

have explained the principle of my invention and have illustrated and described what I now consider to represent its best embodiment. However, I desire to have it understood that, within the scope of the appended claim, the nvention may be practiced otherwise than as specifically illustrated and described.

I claim:

ln a telegraph sending key, a base, a pair of laterally spaced parallel levers above the base, means pivotally mounting each lever on the base on a vertical axis, a stop mounted on the base between the levers and engageable by their inner sides, stationary electric contacts mounted on the base at the outer sides of the levers, an electric contact carried by each lever beside the adjacent stationary contact, manually operable means at one end of the levers for swinging their contact-carrying portions away from each other to move their contacts into engagement with the stationary contacts, a magnet mounted on the outer side of each lever at the contact side of said pivoting means and having outwardly facing north and south poles, a second magnet spaced outwardly from each lever magnet and having inwardly facing north and south poles, each pair of adjacent magnets being disposed with their north poles opposite each other to normally force the levers against said stop, horizontal screws rigidly connected to said second magnets, and means on said base threadedly receiving said screws to support the second magnets and permit them to be adjusted toward and away from the adjacent first-mentioned magnets and simultaneously rotated relative thereto, whereby to vary the pressure of the levers against the stop.

.References Cited bythe Examiner UNITED STATES PATENTS 2,594,071 4/52 Reverchon 178-82 2,850,686 9/58 Macgeorge 317-171 ROBERT H. ROSE, Primary Examiner. 

